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A smart catalyst was fabricated by combining ordered mesoporous silica, Pt nanoparticles with ultra-small size (

Objective The Lauge-Hansen classification provides a detailed description of the mechanism of ankle fracture. Mastering the classification can provide theoretical support for the selection of internal fixation, intraoperative reduction and fixation. Methods We are devoted to creating the image teaching method of “Simulated Wrist Exercise in Hyperextension Position” to help students and young doctors quickly master this classification of ankle fractures. Results In the clinical teaching process,the “Simulated Wrist Exercise in Hyperextension Position” teaching method we used to explain the Lauge-Hansen classification of ankle fractures. The students could memorize the classification and anatomy of ankle joint,and achieved good teaching results. Conclusion This image teaching method of “Simulated Wrist Exercise in Hyperextension Position” simplifies the complex concepts in Lauge-Hansen classification and visualizes the abstract theory. It is worthy of further optimization and promotion.

Fluorescent copper nanoslusters (CuNCs) as a new class of fluorophores have attracted more and more attention due to their ease of synthesis, excellent optical properties, and low cost. In this study, a novel label-free fluorescent method was developed for the detection of DNA methyltransferases based on template length-dependent of dsDNA-CuNCs. In the absence of DNA adenine methylation methyltransferase (Dam MTase), the dsDNA containing the methylation-responsive sequence could effectively template the formation of fluorescent CuNCs with bright fluorescence. When the dsDNA substrate is methylated by Dam MTase, the methylation-sensitive restriction endonuclease Dpn I cleaves the methylated dsDNA and produces shorter dsDNA product, which fails to template fluorescent CuNCs. So, the Dam MTase activity could be identified by the changes of CuNCs' fluorescence. Based on this method, a linear range of 0.5–10 U/mL was achieved with high sensitivity and selectivity. Moreover, we also demonstrate the proposed method can be applied to evaluation and screening of inhibitors for Dam MTase.

There is increased expression of liver x receptor (LXR) target genes and reduced low density lipoprotein receptor (LDLR) during spontaneous luteolysis in primates. The LXRs are nuclear receptors that increase cholesterol efflux by inducing transcription of their target genes. Transcription of LDLR is regulated by sterol regulatory element binding proteins (SREBPs). Human chorionic gonadotropin (hCG) prevents luteolysis and stimulates progesterone synthesis via protein kinase A (PKA). Thus, our primary objectives are: 1) Determine the effects of LXR activation and SREBP inhibition on progesterone secretion and cholesterol metabolism, and 2) Determine whether hCG signaling via PKA regulates transcription of LXR and SREBP target genes in human luteinized granulosa cells. Basal and hCG-stimulated progesterone secretion was significantly decreased by the combined actions of the LXR agonist T0901317 and the SREBP inhibitor fatostatin, which was associated with reduced intracellular cholesterol storage. Expression of LXR target genes in the presence of T0901317 was significantly reduced by hCG, while hCG promoted transcriptional changes that favor LDL uptake. These effects of hCG were reversed by a specific PKA inhibitor. A third objective was to resolve a dilemma concerning LXR regulation of steroidogenic acute regulatory protein (STAR) expression in primate and non-primate steroidogenic cells. T0901317 induced STAR expression and progesterone synthesis in ovine, but not human cells, revealing a key difference between species in LXR regulation of luteal function. Collectively, these data support the hypothesis that LXR-induced cholesterol efflux and reduced LDL uptake via SREBP inhibition mediates luteolysis in primates, which is prevented by hCG.

Multivariate statistical analyses were used to assess the contents and distributions of trace elements in agricultural soils in Xinzhou of Shanxi Province, China, and to identify their sources. Samples with high levels of trace elements were concentrated in eastern Xinzhou, with contents declining from the east to west. Principal component and redundancy analyses revealed strong correlations among Co, Cu, Mn, Ni, Se, V, and Zn contents, suggesting that these elements were derived from similar parent materials. There were also strong correlations between the contents of these elements and soil properties. Contents of Cd and Pb were significantly higher in the agricultural soil samples than in the background soil samples (P

Terahertz (THz) time-domain pulse detection technique has recently attracted great attention in the nondestructive testing (NDT) field due to its superior detection accuracy and sensitivity for various non-metallic materials. However, the dispersion of the THz wave in the tested material significantly degrades the temporal and spatial resolution of THz detection, which limits its practical applications in the high-resolution measurement. Here, a novel dispersion compensation strategy based on the double Gaussian mixture model (DGMM) is proposed to suppress the dispersion effect in THz echoes. The double overcomplete dictionaries composed of one parametric dispersion dictionary and one parametric non-dispersion dictionary are designed separately by discretizing the estimated parameter vector from observed THz echoes. To obtain the excellent performance of dispersion compensation, the convex optimization technique is employed to sparsely decompose the observed dispersive THz echoes by the appropriate selection of the optimal regularization parameter. Both numerical simulations and experiments can validate the effectiveness of proposed method for the non-overlapping and overlapping dispersive THz echoes.

The Lower Silurian Longmaxi shale is the most important marine shale gas play in South China. Several hundred wells have been drilled to date, of which more than 150 wells have obtained high initial production (IP). Outside of the Sichuan Basin, however, wells drilled in the Lower Silurian Longmaxi shale do not reach flow rates that are commercial. Developing an understanding of the key factors controlling the IPs of Longmaxi shale is important in screening shale-resource plays. In this study, the TOC, thermal maturity, porosity, and gas saturation data obtained from Longmaxi shale of southeastern Chongqing area outside Sichuan Basin have been compared with that of Sichuan Basin. The results of this study show that the shales encountered display similar properties including TOC (>2%), thermal maturity (2.5–3.5% EqRo), and total porosity (3–6%). A good correlation between IPs and pressure coefficient suggest that the free gas content of gas shale controls on IPs. Porosity and gas saturation of gas shale are the main factors to control its free gas volume. The gas saturations in Longmaxi shale from high initial production wells in Sichuan Basin mainly range between 50 and 90%, however, that of shale in the southeastern Chongqing area are decreased to 10–30%. This is the directly reason for low IPs of wells. The contrasting gas saturation of Longmaxi shale between Sichuan Basin and the adjacent fold-thrust belts are interpreted to reflect, in part, differences in sealed condition of fluid system. Intensive tectonic movements caused the exhumation, faulting and fracturing, that reduced or destroyed the sealed ability of shale fluid system, which are the major factors for enhancing water saturation, decreasing fluid pressure and IPs. Finally, the study proposes several most favorable zones for Longmaxi shale gas exploration and development.

Terahertz (THz) time-domain detection has emerged as a promising tool for nondestructive testing due to its superior detection accuracy and sensitivity for both interfaces and internal defects inside non-metallic materials. In THz nondestructive evaluation, accurate characterizations of time-of-flight (TOF) extracted from the echo signal are critical to locate the layer interfaces and damages inside the structure. However, for prevalent complex THz echo signals such as overlapping echoes, low signal-to-noise (SNR) echoes and severe dispersion echoes, conventional methods by merely determining the TOF such as the direct method and the deconvolution method might be compromised. Here we have proposed the sparse representation (SR) method to quantitatively characterize the layer thickness by reconstructing the impulse response from complex THz echo signals. To balance the accuracy and the computational efficiency, we have proposed a combinational search method for selecting the optimal regularization parameter and constructed a convolution dictionary based on the structural prior of THz reference echo during the sparse decomposition process. Both numerical and experimental analysis are performed to validate the robustness of SR method on the THz echo localization compared with those conventional methods. It can be expected that SR will provide a novel approach to the application of precise localization and quantification of defects in THz based nondestructive techniques.

Recently, terahertz time-of-flight tomography (THz TOFT) has attracted attention for the localization and quantitative characterization of internal defects in composite materials due to its superior time and spatial resolution and high penetration for various non-metallic materials. However, the dispersion in the THz optical constants and a lack of prior knowledge of defect types in a composite sample significantly degrade the temporal and spatial resolution in THz TOFT measurements, which hinders the super-resolution characterization of the defects internal the material. Here, a sparse Bayesian learning-based (SBL) spectrum-graph integration method is proposed to enable super-resolution characterization of multi-ply glass fiber reinforced polymer (GFRP) composites with delamination defects. The core of this strategy includes spectrum localization and graph quantification. The spectrum-localization process is first implemented to accurately obtain the depth location of delamination defects by SBL, in which dispersion compensation based on double parametric dictionaries is performed to address the dispersion and overlapping issues of the dispersive THz echoes reflected from various interfaces within the sample. Then, based on the estimated depth information for each delamination defect, the graph-quantification process is carried out to characterize the transverse location and size of each delamination defect by the local peak-to-peak stratified imaging method. The estimated size accuracy for the delamination defects can reach more than 95%. Overall, the proposed strategy can quantitatively and simultaneously characterize the axial and transverse information of delamination defects internal GFRP composites with high resolution.

In this paper, a luminescent and thermo-responsive catalyst based on SiO2@Pt@PABI-Tb@PNIPAM was prepared by incorporating Pt nanoparticles, luminescent material and mesoporous silica with thermo-responsive polymer. The obtained catalyst was characterized by IR, TGA, UV–vis, SEM, TEM, X-ray photoelectron spectroscopy and luminescence. The hybrid catalyst exhibits “on-off” green luminescence in solution under UV irradiation, which could be observed by eyes. The catalytic results indicate that the dehydrogenation of ammonia borane (AB) catalyzed by SiO2@Pt@PABI-Tb@PNIPAM is thermo-controllable and switchable. The SiO2@Pt@PABI-Tb@PNIPAM shows high catalytic activity for the generation of hydrogen at room temperature. However, it exhibits much lower catalytic activity at high temperature. The catalysts exhibit excellent durability because the support and polymer could prevent the aggregation and leaching of Pt nanoparticles during catalysis. The catalytic research offers a new approach to the thermo-controllable application in the generation of hydrogen from AB.

A comprehensive investigation of the levels, distribution patterns, and sources of polycyclic aromatic hydrocarbons (PAHs) in agricultural soils of the coal production area surrounding Xinzhou, China, was conducted, and the potential human health risks associated with the levels observed were addressed. A total of 247 samples collected from agricultural soils from the area were analyzed for sixteen PAHs, including highly carcinogenic isomers. The PAH concentrations had a range of n.d. to 782ngg(-1), with a mean value of 202ngg(-1). The two-three ring PAHs were the dominant species, making up 60 percent of total PAHs. Compared with the pollution levels and carcinogenic potential risks reported in other studies, the soil PAH concentrations in the study area were in the low to intermediate range. A positive matrix factorization model indicates that coal/biomass combustion, coal and oil combustion, and coke ovens are the primary PAH sources, accounting for 33 percent, 26 percent, and 24 percent of total PAHs, respectively. The benzo[a]pyrene equivalent (BaPeq) concentrations had a range of n.d. to 476ngg(-1) for PAH7c, with a mean value of 34ngg(-1). The BaPeq concentrations of PAH7c accounted for more than 99 percent of the ∑PAH16, which suggests that seven PAHs were major carcinogenic contributors of ∑PAH16. According to the Canadian Soil Quality Guidelines, only six of the soil samples had concentrations above the safe BaPeq value of 600ngg(-1); the elevated concentrations observed at these sites can be attributed to coal combustion and industrial activities. Exposure to these soils through direct contact probably poses a significant risk to human health as a result of the carcinogenic effects of PAHs.

The conversion of fructose into 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) was investigated and catalyzed by indium trichloride (InCl 3 ) in water. 79% 5-HMF yield (15 min) and 45% LA yield (60 min) were obtained at 180 °C with 2.5 mol% InCl 3 . Additionally, comparative studies of glucose/fructose mixture with different ratios as substrates were carried out to manifest the isomerization process between glucose and fructose during the conversion of monosaccharides into chemicals. It was shown that InCl 3 was not only active in the isomerization of glucose to fructose and the reverse direction, but also demonstrated an excellent activity in the dehydration and conversion of monosaccharides. InCl 3 –H 2 O system presented a remarkable catalytic effect on the dehydration and conversion of monosaccharides.

A state-owned glass production enterprise introduces the strategic investor to carry on the assets reorganization, including the purchase of two float glass production lines with subsequent technology transformations and the construction of a new float glass production line with domestic leading technology. The fuel consumption structure has changed from coal-burning to natural gas or fuel oil. The following auditing procedures were followed according to Chinese national standards. These procedures include constituting an ordinance on energy management, strengthening the energy measurement and data statistical system, and improving production lines as well as energy-saving measures. Production scale expanded approximately twice during the period of audit. Comprehensive energy consumption was 2.58 ton coal equivalent (tce) at aqual in heat value (AHV refers to energy consumed to generate each kW h of electric power, each m 3 of oxygen, nitrogen, hydrogen, or each kg of steam. The term of AHV provides a unification measurement criterion for fossil fuels consumed before the energy transformation.) account per 10,000 Yuan output value, and 2.17 tce at heat value equivalent (HVE) account. Comprehensive energy consumption per unit of product was 15.35 kg coal equivalent (kce) per weight box. The percentage of energy cost among total cost reduced from 51.19% in 2007 to 46.48% in 2008. Consequently, the comprehensive energy conversion level holds a leading position among peers in China.

The photophysical properties of 1,1′-binaphthyl-2,2′-diyl hydrogenphosphate (BNP) have been examined with particular emphasis to the effects of the chiral recognition of BNP by α-, β-, and γ-cyclodextrins (CDs). Fluorescence spectra and anisotropy values of the BNP enantiomers were measured in the presence and absence of the CDs under various conditions and the chiral recognition behavior are discussed based on the acquired fluorescence data. Small spectral shifts in the fluorescence emission allowed evaluation of the binding constant and enantioselectivity of the binding in β-, and γ-cyclodextrin, but significant shifts were not observed in the case of α-cyclodextrin. Fluorescence anisotropy proved to be an effective technique to study the enantioselective interactions, even in the case of α-cyclodextrin where a smaller binding constant and enantiodiscrimination were confirmed. The differential thermodynamics of binding were examined by fluorescence anisotropy and are discussed with reference to the general structural characteristic of the cyclodextrins examined. Interestingly, BNP was found to exhibit opposite thermodynamic trends for β-cyclodextrin at low (1 mM) and high (11 mM) cyclodextrin concentrations, indicating the possibility of complex of even different modes of enantiodiscrimination in this system.

The photophysical properties of [1,1′-binaphthalene]-2,2′-diol (BINOL) have been examined with particular emphasis to the effects of chirality and chiral recognition. Few studies have specifically examined the photophysical properties of BINOL. This study was prompted by preliminary observations in our laboratory that revealed anomalously high fluorescence anisotropy values for BINOL. The analyte (BINOL) was examined in various solvents and in aqueous solutions of various pH values in order to perturb the effects of proton transfer, which was observed as a red-shift in the fluorescence emission. The anomalously high anisotropy value could not, however, be attributed to proton transfer phenomena. The anisotropy was found to be concentration dependent and was attributed to the formation of dimers or other higher order aggregates. The chiral recognition of BINOL was also examined by fluorescence anisotropy measurements and compared to that of other binaphthyl analogs.

Boron nitride (BN) with flake-like morphology has been synthesized by reacting powder H3BO3, Mg and NH4Cl in an autoclave at 600 °C for 10 h. X-ray diffraction (XRD) patterns show the sample has hexagonal phase with lattice parameters a = 2.506 and c = 6.692 A. Transmission electron microscopy (TEM) and field emission scanning electron (FE-SEM) indicate the as-synthesized product is pure flake with a mean size of about 100 nm in thickness and 600 nm in width length. X-ray photoelectron spectra (XPS) give an average B/N atomic ratio of 0.98:1. Fourier transformation infrared spectroscopy (FTIR) has a strong B–N absorption at 1376 cm− 1 and 814 cm− 1.